Technical Field
The present disclosure relates generally to an anvil assembly which is suitable for use with a circular anastomosis stapler. More specifically, the present disclosure relates to an anvil assembly having a tiltable head with a sliding sleeve.
Background of Related Art
Circular anastomosis staplers which include an anvil assembly having a tiltable anvil head are known in the art. One such circular anastomosis stapler is disclosed in commonly owned U.S. Pat. No. 8,109,426 (“the '426 Patent”) which is incorporated herein by reference in its entirety. The anvil assembly includes an anvil head pivotally secured on a distal end of a connection post of the anvil assembly. The anvil assembly is pivotable from a first tilted position to facilitate insertion of the anvil assembly trans-orally, to a non-tilted operative position wherein the anvil head is perpendicular to the connection post. Following the firing operation of the circular stapler and as the anvil head is separated from the cartridge assembly of the circular stapler, the anvil head continues to pivot about the distal end of the connection post to a second tilted position, thereby reducing the profile of the anvil head to permit removal of the anvil assembly through the newly created anastomosis ring. The anvil assembly is spring loaded to tilt to a maximum angle allowed by the circular stapler and/or anvil head geometry. Tilting the anvil head to its maximum angle facilitates pulling the anvil head through the anastomosis ring and removing the anvil assembly from within the patient.
In certain instances, an anastomosis donut, i.e., the tissue severed by an annular knife of the stapling assembly during the anastomosis procedure, may become pinched by the anvil head as the anvil head is pivoted. When pinching of the anastomosis donut occurs, the anvil head is inhibited from tilting to its maximum angle. As a result, the anvil head may require a greater force to withdraw the anvil head through the anastomosis ring, thereby causing undesirable and unnecessary trauma to the anastomosis ring and/or.
Therefore, it would be beneficial to have an anvil assembly that prevents pinching of tissue or another obstruction by the tiltable anvil head, and, thus, allow complete tilting of the anvil head.